Re: [2.6.6-BK] x86_64 has buggy ffs() implementation

From: Andi Kleen
Date: Wed May 12 2004 - 09:04:05 EST

On Wed, 12 May 2004 14:43:37 +0100
Anton Altaparmakov <aia21@xxxxxxxxx> wrote:

> Hi Andi, Andrew, Linus,
> x86_64 has incorrect include/asm-x86_64/bitops.h::ffs() implementation.
> It uses "g" instead of "rm" in the insline assembled bsfl instruction.
> (This was spotted by Yuri Per.)
> bsfl does not accept constant values but only memory ones. On i386 the
> correct "rm" is used.
> This causes NTFS build to fail as gcc optimizes a variable into a
> constant and ffs() then fails to assemble.
> Please apply below patch. Thanks!

Thanks. I applied it to my tree.

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